Electrical therapy has long been used in medicine to treat pain and other conditions. For example, transcutaneous electrical nerve stimulation (TENS) systems deliver electrical energy through electrode patches placed on the surface of a patient's skin to treat pain in tissue beneath and around the location of the patches. The efficacy of TENS systems in alleviating pain is questionable at best, however.
More recently, a technique in which electrodes are placed through the patient's skin into the target tissue has been proposed. Percutaneous Neuromodulation Therapy (“PNT”) (also sometimes called Percutaneous Electrical Nerve Stimulation or “PENS”) using percutaneously placed electrodes achieves significantly better pain relief results than TENS treatments using skin surface electrodes. This therapy is described in Ghoname et al., “Percutaneous Electrical Nerve Stimulation for Low Back Pain,” JAMA 281:818-23 (1999); Ghoname et al.; “The Effect of Stimulus Frequency on the Analgesic Response to Percutaneous Electrical Nerve Stimulation in Patients with Chronic Low Back Pain,” Anesth. Analg. 88:841-6 (1999); Ahmed et al., “Percutaneous Electrical Nerve Stimulation (PENS): A Complementary Therapy for the Management of Pain Secondary to Bony Metastasis,” Clinical Journal of Pain 14:320-3 (1998); and Ahmed et al., “Percutaneous Electrical Nerve Stimulation: An Alternative to Antiviral Drugs for Herpes Zoster,” Anesth. Analg. 87:911-4 (1998). The contents of these references are incorporated herein by reference.
One drawback with some existing PNT techniques is that it can be difficult for practitioners to accurately determine how far the percutaneous electrode is inserted beneath the patient's skin. As a result, the practitioner may not position the electrode at the most effective location, and accordingly may not deliver treatment in an optimal fashion. Another drawback with some existing PNT techniques is that the electrode can be difficult to manipulate, keep track of, and/or work around, particularly when multiple electrodes are used simultaneously on a relatively small portion of the patient's body.